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docs/src/worktree_working.md

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+# Working with Worktrees
+
+## Creating a new worktree
+
+To actually work, you'll first have to create a new worktree checkout. All
+worktree-related commands are available as subcommands of `grm worktree` (or
+`grm wt` for short):
+
+```
+$ grm wt add mybranch
+[✔] Worktree mybranch created
+```
+
+You'll see that there is now a directory called `mybranch` that contains a
+checkout of your repository, using the branch `mybranch`
+
+```bash
+$ cd ./mybranch && git status
+On branch mybranch
+nothing to commit, working tree clean
+```
+
+You can work in this repository as usual. Make changes, commit them, revert
+them, whatever you're up to :)
+
+Just note that you *should* not change the branch inside the worktree directory.
+There is nothing preventing you from doing so, but you will notice that you'll
+run into problems when trying to remove a worktree (more on that later). It may
+also lead to confusing behavior, as there can be no two worktrees that have the
+same branch checked out. So if you decide to use the worktree setup, go all in,
+let `grm` manage your branches and bury `git branch` (and `git checkout -b`).
+
+You will notice that there is no tracking branch set up for the new branch. You
+can of course set up one manually after creating the worktree, but there is an
+easier way, using the `--track` flag during creation. Let's create another
+worktree. Go back to the root of the repository, and run:
+
+```bash
+$ grm wt add mybranch2 --track origin/mybranch2
+[✔] Worktree mybranch2 created
+```
+
+You'll see that this branch is now tracking `mybranch` on the `origin` remote:
+
+```bash
+$ cd ./mybranch2 && git status
+On branch mybranch
+
+Your branch is up to date with 'origin/mybranch2'.
+nothing to commit, working tree clean
+```
+
+The behavior of `--track` differs depending on the existence of the remote
+branch:
+
+* If the remote branch already exists, `grm` uses it as the base of the new
+  local branch.
+* If the remote branch does not exist (as in our example), `grm` will create a
+  new remote tracking branch, using the default branch (either `main` or
+  `master`) as the base
+
+Often, you'll have a workflow that uses tracking branches by default. It would
+be quite tedious to add `--track` every single time. Luckily, the `grm.toml`
+file supports defaults for the tracking behavior. See this for an example:
+
+```toml
+[track]
+default = true
+default_remote = "origin"
+```
+
+This will set up a tracking branch on `origin` that has the same name as the
+local branch.
+
+Sometimes, you might want to have a certain prefix for all your tracking
+branches.  Maybe to prevent collisions with other contributors. You can simply
+set `default_remote_prefix` in `grm.toml`:
+
+```toml
+[track]
+default = true
+default_remote = "origin"
+default_remote_prefix = "myname"
+```
+
+When using branch `my-feature-branch`, the remote tracking branch would be
+`origin/myname/my-feature-branch` in this case.
+
+Note that `--track` overrides any configuration in `grm.toml`. If you want to
+disable tracking, use `--no-track`.
+
+## Showing the status of your worktrees
+
+There is a handy little command that will show your an overview over all
+worktrees in a repository, including their status (i.e. changes files). Just run
+the following in the root of your repository:
+
+```
+$ grm wt status
+╭───────────┬────────┬──────────┬──────────────────╮
+│ Worktree  ┆ Status ┆ Branch   ┆ Remote branch    │
+╞═══════════╪════════╪══════════╪══════════════════╡
+│ mybranch  ┆ ✔      ┆ mybranch ┆                  │
+│ mybranch2 ┆ ✔      ┆ mybranch ┆ origin/mybranch2 │
+╰───────────┴────────┴──────────┴──────────────────╯
+```
+
+The "Status" column would show any uncommitted changes (new / modified / deleted
+files) and the "Remote branch" would show differences to the remote branch (e.g.
+if there are new pushes to the remote branch that are not yet incorporated into
+your local branch).
+
+
+## Deleting worktrees
+
+If you're done with your worktrees, use `grm wt delete` to delete them. Let's
+start with `mybranch2`:
+
+```
+$ grm wt delete mybranch2
+[✔] Worktree mybranch2 deleted
+```
+
+Easy. On to `mybranch`:
+
+```
+$ grm wt delete mybranch
+[!] Changes in worktree: No remote tracking branch for branch mybranch found. Refusing to delete
+```
+
+Hmmm. `grm` tells you:
+
+"Hey, there is no remote branch that you could have pushed your changes to. I'd
+rather not delete work that you cannot recover."
+
+Note that `grm` is very cautious here. As your repository will not be deleted,
+you could still recover the commits via
+[`git-reflog`](https://git-scm.com/docs/git-reflog).  But better safe than
+sorry! Note that you'd get a similar error message if your worktree had any
+uncommitted files, for the same reason. Now you can either commit & push your
+changes, or your tell `grm` that you know what you're doing:
+
+```
+$ grm wt delete mybranch --force
+[✔] Worktree mybranch deleted
+```
+
+If you just want to delete all worktrees that do not contain any changes, you
+can also use the following:
+
+```
+$ grm wt clean
+```
+
+Note that this will not delete the default branch of the repository. It can of
+course still be delete with `grm wt delete` if necessary.
+
+### Converting an existing repository
+
+It is possible to convert an existing directory to a worktree setup, using `grm
+wt convert`. This command has to be run in the root of the repository you want
+to convert:
+
+```
+$ grm wt convert
+[✔] Conversion successful
+```
+
+This command will refuse to run if you have any changes in your repository.
+Commit them and try again!
+
+Afterwards, the directory is empty, as there are no worktrees checked out yet.
+Now you can use the usual commands to set up worktrees.